[MEncoder-users] Converting raw grayscale stream to xvid or other video

[Sarag]

Hello,
  I have had luck in the past using mencoder on encoding raw files
consisting of rgb32 values with xvid. However, I now find myself in need of
encoding raw files made up of grayscale values.

The command I used in the past was:
mencoder ../raw/full.raw -rawvideo w=1024:h=768:fps=
24.0:size=3145728:format=RGB32 -ovc xvid -xvidencopts
bitrate=300:gmc:chroma_me:chroma_opt:hq_ac:vhq=4:pass=1 -lameopts
cbr:preset=80 -noskip -oac copy -o output.avi

Or:
mencoder -ovc lavc -lavcopts
vcodec=msmpeg4v2:vpass=1:vbitrate=3840000:mbd=2:keyint=132:vqblur=
1.0:cmp=2:subcmp=2:dia=2:mv0:last_pred=3 -nosound -o /dev/null
../raw/red.raw -rawvideo w=1024:h=768:fps=24.0:size=3145728:format=RGB32

Which worked for me. However, how do I specify grayscale? I am not finding
what I need in the documentation or manpage.

Thanks in advance and cheers.